The Newsletter for Marshall University
November 30, 2011

Marshall University study shows nanoparticles being used
as additives in diesel fuels can travel from lungs to liver,
causing damage

Recent studies conducted at Marshall University have demonstrated that
nanoparticles of cerium oxide – common diesel fuel additives used to increase
the fuel efficiency of automobile engines – can travel from the lungs to the
liver and that this process is associated with liver damage.

The data in the study by Dr. Eric R. Blough and his colleagues at MU’s Center
for Diagnostic Nanosystems indicate there is a dose-dependent increase in the
concentration of cerium in the liver of animals that had been exposed to the
nanoparticles, which are only about 1/40,000 times as large as the width of a
human hair. These increases in cerium were associated with elevations of liver
enzymes in the blood and histological evidence consistent with liver damage. The
research was published in the Oct. 13 issue of the peer-reviewed research
journal International Journal of Nanomedicine.

Cerium oxide is widely used as a polishing agent for glass mirrors, television
tubes and ophthalmic lenses. Cerium oxide nanoparticles are used in the
automobile industry to increase fuel efficiency and reduce particulate
emissions. Some studies have found that cerium oxide nanoparticles may also be
capable of acting as antioxidants, leading researchers to suggest these
particles may also be useful for the treatment of cardiovascular disease,
neurodegenerative disease and radiation-induced tissue damage.

Blough, the center’s director and an associate professor in Biological Sciences,
said, “Given the ever-increasing use of nanomaterials in industry and in the
products we buy, it is becoming increasingly important to understand if these
substances may be harmful. To our knowledge, this is the first report to
evaluate if inhaled cerium oxide nanoparticles exhibit toxic effects in the
liver.”

Dr. Siva K. Nalabotu, the study’s lead author and a Ph.D. student in Blough’s
lab, said, “The potential effects of nanomaterials on the environment and
cellular function is not yet well understood. Interest in nanotoxicity is
rapidly growing.

“Our studies show that cerium oxide nanoparticles are capable of entering the
liver from the lungs through the circulation, where they show dose-dependent
toxic effects on the liver. Our next step is to determine the mechanism of the
toxicity.”

The research was supported with funding from the U.S. Department of Energy.